ABSTRACT
The purpose of present study was to investigate the cerebral oxygenation and oxygen uptake (VO<sub>2</sub>) during exercise of a combined circuit training (CCT) and a circuit resistance training (CRT). Nine healthy young male subjects performed the following two trails on separate days: 1) CCT trail (three circuits of aerobic exercise for 5 min at 50%VO<sub>2</sub>max and 1 set of four resistance exercises at 50% one-repetition maximum) and 2) CRT trail (six circuits of the same resistance exercises and intensity as for CCT without aerobic exercise). Exercise duration of these trails was 30 minutes. Cerebral oxygenation was determined by near infrared spectroscopy, and VO<sub>2</sub> was measured by breath by breath methods. Cerebral oxygenation and VO<sub>2</sub> were continuously monitored during the exercise. Oxyhemoglobin and total hemoglobin concentration during CCT trail was significantly higher than during CRT trail (<i>p</i><0.05). Average VO<sub>2</sub> and energy expenditure during CCT trail were significantly higher than during CRT trail (<i>p</i><0.05). These results suggest that a single bout of circuit resistance training combined with aerobic exercise induced greater energy expenditure and cerebral oxygenation than those induced by a resistance training with the same exercise duration.
ABSTRACT
The purpose of this study was to investigate the acute effects on excess post-exercise oxygen consumption (EPOC) of low intensity and slow-movement repetitive resistance exercise in moderately trained young men. Seven healthy trained young men (age=22±3 yr ; height=172.5±4.0 cm ; weight=69.5±8.3 kg ; VO<sub>2</sub>max=47.3±6.0 ml/kg/min) performed the following three exercise patterns on separate days : 1) high-intensity (80% one-repetition maximum : 1RM) and regular-movement repetitive exercise (1 second each of concentric and eccentric action, termed high and regular exercise (HRE) ; 2) low-intensity (50%1RM), regular-movement repetitive exercise (same movement speed as for HRE but termed low and regular exercise (LRE); and 3) low-intensity (50%1RM), slow-movement repetitive exercise (4 sec each of concentric and eccentric action, termed low and slow exercise (LSE). These three exercise patterns consisted of three sets of four exercises performed to maximum repetition. All subjects completed the three exercise sessions in a randomized and counterbalanced fashion. Oxygen consumption (VO<sub>2</sub>) and heart rate (HR) were continuously monitored during the exercise sessions and for 90 min afterwards. EPOC over 90 min was thus observed after completing the three exercise patterns. However, there were no significant differences in EPOC among the three exercise patterns. The results of this study suggest that low-intensity and slow-movement repetitive resistance exercise with maintaining muscular tension (LSE) is likely to increase EPOC to the same extent as HRE and LRE exercise patterns.
ABSTRACT
The purpose of this study was to evaluate the fat-free mass (FFM) of the total body, the upper limbs, and the lower limbs in healthy subjects and basketball players obtained by the new 8-electrode segmental bioelectrical impedance analysis (S-BIA) and to compare the results with the FFM obtained by DXA. The participants were 30 healthy subjects (15 men and 15 women) aged 24.9±3.5 years old and 15 female basketball players aged 23.1±3.1 years old. In the healthy subjects, positive correlations (p<0.001) were observed between the FFM obtained by S-BIA and DXA of the total body (r=0.973), the upper limbs (r=0.956), and the lower limbs (r=0.954). Similarly, in the basketball players, positive correlations (p<0.001, p<0.01) were observed between the FFM obtained by S-BIA and DXA of the total body (r=0.943), the upper limbs (r=0.743), and the lower limbs (r=0.934). The results suggest that the new 8-electrode S-BIA is a valid and convenient method for analyzing body composition of the total body and the body segments in healthy subjects and athletes.
ABSTRACT
The purpose of this study was to investigate the intensity of exercise load which increases urinary 8-hydroxydeoxyguanosine (8-OHdG) excretion and the effect of antioxidant supplementation on urinary 8-OHdG excretion after a single bout of exercise. The subjects included 6 healthy males with the following characteristics : age ; 24.0±1.1 years, height ; 174.0±8.5 cm, weight ; 71.5±15.4 kg, BMI ; 23.2±3.4 kg/m<sup>2</sup>. The urinary concentration of 8-OHdG was measured by the two-column-switching high-performance liquid chromatography (HPLC) method. After 7 days of supplementation, the time course of the urinary 8-OHdG excretion was observed following treadmill running at 70% VO<sub>2</sub>max.Significant increases in the urinary 8-OHdG excretion were detected at 2 h (p<0.01) and 4 h (p<0.05) after exercise.After 7 days of supplementation, a significant increase in the urinary 8-OHdG excretion was detected 1 h after exercise (p<0.05); however, it returned to the initial level 2 h after exercise. Therefore, oxidative DNA damage induced by a single bout of exercise was diminished by antioxidant supplementation.
ABSTRACT
15 healthy elderly adults (68.6±4.5 years old) participated in this study and were chosen at random for either super low-velocity repetition training (SLT : n=7) or general low-velocity repetition training (GLT : n=8). All subjects performed machine training leg work twice a week for 6 months. Training contents of SLT and GLT were programmed as follows : SLT (Method : 4 seconds of lifting and 6 sec of lowering) and GLT (Method : 2 sec of lifting and 2 sec of lowering). Muscular strength testing was adopted during isometric knee extension using Cybex6000, and body composition was measured by DXA method. As a result, increases in peak torque values and 5 sec average torques value were significantly different in both groups, pre- and post-training (p<0.05). However, there was no significant difference between the two groups. Fat mass significantly decreased during post-training in both groups (p<0.05); however, there was no significant difference between the groups. SLT showed that increases in maximum muscular strength and endurance were similar to GLT. Thus, low-intensity and low-velocity repetition training is suggested as an effective method for elderly adults to increase lower limb muscular strength.
ABSTRACT
Detection of the coronary artery is usually an easy procedure in the coronary artery surgery. However in cases with an intra-muscular and/or intra-fat coronary artery, it requires special skill and experience. Dissection of epicardial adipose tissue and/or muscle along the epicardial groove is a common procedure to reach such coronary artery in conventional CABG (C-CABG). Recently, off-pump CABG (OPCAB) has become a standard operation, and detection of such a coronary artery is difficult under the beating heart. Then conversion to the C-CABG becomes necessary to avoid ventricular rupture. We report a new procedure to easily detect such a coronary artery in OPCAB, using an ultrasonic Fowmeter used in neurosurgery. Because the tip of the probe is small (2mm in diameter) and flexible, its handling is quite similar to that of the micro-blade knife. Furthermore, audiable Doppler flow sound allows detection and dissection of the coronary artery without looking away from the operative field to check the coronary flow. In our case, use of the instrument enabled us to detect the anterior descending branch of the left coronary artery which was very deep in adipose tissue. Therefore, application of this ultrasound instrument is beneficial in OPCAB with an intra-muscular and/or intra-fat coronary artery.